Sorry for the delay Marcel. I am very busy suddenly, but still working on this problem also. Thanks for the "late night" comments. You are 6 hours ahead of me always

Regarding...

B
We could also use participant_id to tie the multiple surveys together, as long as they aren't anonymous, I think

C
I almost never use default answers and didn't think of trying that trick. The only glitch is this requirement: "The question for which you set the default answer has to be shown on a following page." In most cases the formulas are all on the same page with their inputs, so the default may not be available yet (until the next page). I'll try it out.

@B: That might work as well.

@C: It "might" also work on the same page but I didn't test that yet. Having it on the next page is definitely safer.

For calculation, best is tu use Équation and not default answers, no ?

Denis

Why?

Using my approach you should be able to easily put several formulas into one question instead of setting up a new question for each one.

Ah yes,

You're right. Think the best is:
Use Équation for question where équation are OK
Use javascript other time (for example for TOTAL sub value (readonly), or user enter sur total ifhe don't know subvalue.

Denis

For now I'm trying single numerics and/or equations for all questions.

1) For each of the calculations we need a relevance expression to make sure all the inputs are there. So a numeric lets you have a unique relevance for each calculation vs. a multi-numeric where you have one for all the subquestions

2) There is some metadata about the calculations that we are storing in question attributes and so, again, using numerics lets us set the attributes for each one separately, rather than a multinumeric where the subquestions share most of the same attributes.

3) We want to save all the calculations to the DB and I prefer having the formula themselves saved in the question record for posterity (rather than in javascript).

4) We are going to be moving everything around with javascript anyway, so the presentation structure of multinumerics and arrays isn't necessary and can even be a hindrance.

5) There WILL be a lot of questions to create, but there is a lot of repetition in the structure and I'm trying to us Excel as a kind of "question factory" to build the codes, relevance expressions, and equations, etc.

Fred wrote: For an easy way to add lots of questions into Limesurvey, have a look at the Excel import: docs.limesurvey.org/Excel+Survey+Structu...tions+for+LimeSurvey

If you are relying on certain question IDs when using JavaScript to customize the question alignment, doing several imports of the Excel survey might cause problems though.
In this case, try using Em placholderhers within the JS code, assuming that the code is put at the question source text or the like (template.js does not get parsed by EM.

This way, you can let EM add the QID dynamically:
var question = {questioncode.qid};